The present invention relates to a half-fitting prevention connector, used for electrically connecting wire harnesses in an automobile together, in which the condition of half-fitting between a pair of male and female connectors is detected through resiliency (urging force) of resilient members.
There have heretofore been known various types of half-fitting prevention connectors in which the condition of half-fitting between a pair of male and female connectors can be detected. One such example is disclosed in Unexamined Japanese Utility Model Publication No. 5-81967. FIG. 5 is a partly-broken, exploded perspective view of the related half-fitting prevention connector.
This related half-fitting prevention connector 51 comprises a pair of male and female connectors 54 and 55 having male terminals 52 and female terminals 53 mounted therein, respectively. Springs (resilient members) 56, acting in an anti-fitting direction, are mounted on the female connector 55, and lock mechanisms 57 are provided at the male and female connectors 54 and 55.
The male connector 54 has a box-shaped body with open front and rear sides, which is formed by a top plate 58, a bottom plate 59 and side plates 60, and the plurality of male terminals 52 are received in this male connector. The male connector can be fitted into the female connector 55, and the male terminals 52 can be fitted respectively into the female terminals 53, received in the female connector 55, to be electrically connected thereto.
A notch is formed in a central portion of each of the opposite side plates 60, and a retaining piece portion 61, serving as part of the lock mechanism 57, is formed integrally with the side plate 60, and extends forwardly in this notch. A distal end of the retaining piece portion 61 is disposed slightly rearwardly of a front edge of the side plate 60, and is so elastic as to be slightly bent (elastically deformed) outwardly. An inwardly-projecting retaining claw 62 is formed on an inner face of the front end portion of the retaining piece portion 61.
Spring receiving portions 63 are formed respectively at opposite sides of the female connector 55, and each spring receiving portion 63 receives the associated spring 56, and supports a rear end thereof. A spring guide rod 64 is provided within the spring receiving portion 63, and extends forwardly. A movable cover (slide member) 65 of a tubular shape with open front and rear sides, is mounted on the outer periphery of the female connector 55 for sliding movement in forward and backward directions. Spring receiving portions 66 are formed respectively at opposite sides of the movable cover 65, and cover the spring receiving portions 63, respectively. The front end of each spring 56 acts on the front end of the associated spring receiving portion 66 to urge the same forward. A retaining hole 70, serving as part of the lock mechanism 57, is formed in each of opposite side plates of the female connector 55.
Slots 67, formed through a top plate the movable cover 65, and projections 68, formed on a top plate of the female connector 55, serve to limit the forward movement of the movable cover 65 under the influence of the springs 56.
In the half-fitting prevention connector 51 of the above construction, when the pair of male and female connectors 54 and 55 are mated with each other at their front ends, and are pressed against each other, the front portion of the female connector 55 is first fitted into the front portion of the male connector 54, and then each retaining claw 62 slides over the side plate 69 of the female connector 55 while flexing the retaining piece portion 61 outwardly. As a result, the distal end of the retaining piece portion 61 and the retaining claw 62 abut against the front end surface of the associated spring receiving portion 66, so that the movable cover 65 is moved rearward while compressing the spring 56.
At this time, when the pair of male and female connectors 54 and 55 are pressed relative to each other, each spring 56 is further compressed, and each retaining claw 62 is retainingly engaged in the associated retaining hole 70, so that the flexed retaining piece portion 61 is restored into its original condition, and also the front end of the retaining piece portion 61 is disengaged from the front end surface of the spring receiving portion 66. Then, when the above pressing force is reduced or removed, the movable cover 65 is returned into its original position by the urging force of the springs 56, and the male and female connectors 54 and 55 are completely fitted together. At the same time, the male terminals 52 are completely connected to the female terminals 53, respectively. The outer faces of the side plates 60 are held in contact with the inner faces of the spring receiving portions 66, respectively, and therefore each retaining piece portion 61 can not be flexed outwardly. Therefore, each retaining claw 62 will not be disengaged from the associated retaining hole 70, and the male and female connectors 54 and 55 are completely locked relative to each other by the lock mechanisms 57.
However, if the pressing force for fitting purposes is reduced or removed in a condition of half-fitting between the pair of male and female connector, that is, before the retaining claw 62 of each lock mechanism 57 is retainingly engaged in the associated retaining hole 70, the male connector 54 is pushed back by the urging force of the springs 56, and therefore the connector is prevented from remaining in such a half-fitted condition.
In the above related half-fitting prevention connector 51, however, the pair of retaining piece portions 61 are provided respectively at the right and left sides, and therefore depending on the mounting positions of the male and female connectors 54 and 55 and on the fitting direction, there were encountered problems that the right and left forces failed to be uniformly applied when the male and female connectors were forcibly fitted together in a tilted manner, that the timing of engagement of the retaining claw 62 of one of the retaining piece portions 61 in the retaining hole 70 is different from the timing of engagement of the other retaining claw 62 in the retaining hole 70, and that only one of the retaining claws 62 was fitted into the retaining hole 70, and in these cases the connector remained in a half-fitted condition.
The male connector 54 is, in many cases, fixedly mounted on a vehicle body, and therefore is usually made of a rigid synthetic resin, such as a glass-containing resin, exhibiting little elasticity, and each time the pair of male and female connectors 54 and 55 are fitted and connected together, each retaining piece portion 61 is flexed outwardly. Furthermore, the distal end of the retaining piece portion 61 is pressed against the front end surface of the spring receiving portion 66 to compress the spring 56, and therefore when the connector is repeatedly operated, the retaining piece portions 61 are subjected to fatigue failure, and this problem must be overcome in order to achieve the high reliability of the connector.